Adopting a breeding program appropriate to the production system helps genetic improvement and reduces incompatibility of genotype with farmer breeding objectives and production system and production environment which aimed at improving preferred traits. In this study, breeding does comprise a dominant part of the flock followed by kids between 6 months to one year. The higher proportion of adult females than other age groups across both study areas indicates the practice of retaining females for breeding (Table 1). This is due to the fact that goat keepers in the pastoral production system possessed significantly large proportions of female goats for breeding and occasionally for milk consumption. This result is in line with the work of Solomon et al. (2010) the proportion of different classes of animals reflects the management decision of the producers which in turn is determined by their production objectives. The ratio of males to females in both districts at the age of fewer than six months was proportional. However, female proportions were higher than males at the age of greater than one year in both districts. This is because male goats were frequently sold whenever cash is needed and farmers did not prefer female goats for meat purposes. This finding was in agreement with the result of Grum (2010) in the Dire Dawa zone, Mahilet (2012) in Eastern Hararghe, and Tesfaye (2010) for the Arsi-Bale goat population, in which the proportion of females is higher than a male goat. However pastoral and agro-pastorals keep a higher proportion of females reflecting the owners' need for milk for long periods in the hot environment (Farm-Africa, 1996 and Alefe, 2014).
Farmers in the study area sell out young goats well-conditioned male goats to earn a better price. This trend of selling early maturing and having fast growth male goats may affect the improvement of the flock in consecutive generations. The ratio between males greater than one year of age and their female counterparts in Abaya and Galan districts was 1:3 and 1:2 respectively. This result is contradictory with that of Adugna (1998) who explains 1:4 in Kochore district, southern Ethiopia, and Wilson (1989) who explained the ratios 1:4 to 1:6 a standard for small ruminants in traditional livestock production systems of Africa. This was due to the study area holding a small number of goats per flock. In this study, a small number of breeding males and females may bring a high rate of inbreeding.
Goat breeding practices
The genetic improvement is cumulative and eventually leads goats to mature earlier in Galan than Abaya, which is indeed a directional/natural selection. Moreover, it is not uncommon that goat herders in different localities have their own trait preferences and selection criteria based on existing production environments, market demands, and other factors that lead to variation in selection criteria. For instance, Gebrekiros (2014) reported that farmers in Western Tigray prioritize the twining ability of goats over any other traits in Begait/Barka goats.
Selection Criteria for Breeding Buck
The selection criteria of breeding bucks are indicated in Table 2. The selection of stock for breeding purposes is a prerequisite to replace better stocks by considering its own morphological, adaptive, and production characteristics. In this study traits like conformation, growth rate, coat color, pedigree, and age were considered as important traits in selecting breeding buck. In Abaya district conformation/appearance, color (white and red), and growth rate of buck were ranked 1st, 2nd, and 3rd, respectively. The corresponding rankings for the Galan district were, conformation/appearance followed by the growth rate, color, and age of buck.
However, goat herders in both districts commonly focus on body conformation (long leg) to select breeding buck, which is indeed highly associated with genetic performances. This indicates that goat herders have their ways of ranking traits based on the purposes they keep. This result was in agreement with the finding of Belete (2013) who reported that farmers select their buck by considering appearance in the Bale zone which is similar production (crop-livestock) system with study area. Selecting buck by growth rate was more practiced in Galan than Abaya. This might be associated with the fact that Galan is a district known as a hub for growing cash crops, mainly coffee that created a market opportunity for goat herders in the areas to focus on the fast growth rate for better prices.
Table 2
Ranking selection criteria of breeding buck
Selection criteria
|
Abaya
|
Galan
|
|
R1
|
R2
|
R3
|
I
|
R1
|
R2
|
R3
|
I
|
Conformation
|
78
|
7
|
2
|
0.46
|
74
|
7
|
1
|
0.44
|
Color
|
0
|
39
|
26
|
0.19
|
4
|
10
|
22
|
0.10
|
Horn
|
0
|
4
|
8
|
0.03
|
0
|
1
|
1
|
0.01
|
Character
|
0
|
0
|
7
|
0.01
|
4
|
4
|
2
|
0.04
|
Adaptability
|
0
|
0
|
2
|
0.00
|
0
|
3
|
11
|
0.03
|
Growth rate
|
8
|
15
|
24
|
0.14
|
8
|
38
|
14
|
0.21
|
Age
|
0
|
4
|
7
|
0.03
|
0
|
20
|
8
|
0.09
|
Libido
|
0
|
3
|
0
|
0.01
|
0
|
4
|
16
|
0.04
|
Pedigree
|
4
|
18
|
14
|
0.11
|
0
|
3
|
15
|
0.04
|
I= index and R= rank |
Selection Criteria for Breeding Doe
Selection criteria of breeding doe in the study area are presented in Table 3. According to the respondents' opinion, conformation/appearance is the main criteria for the selection of doe in both districts. However while twining ability ranked second in Abaya district, age at sexual maturity was given the second priority in Galan.
Table 3
Ranking selection criteria for breeding doe
Selection criteria
|
Abaya
|
Galan
|
R1
|
R2
|
R3
|
I
|
R1
|
R2
|
R3
|
I
|
Conformation
|
78
|
2
|
6
|
0.45
|
77
|
5
|
0
|
0.45
|
Color
|
0
|
25
|
18
|
0.13
|
2
|
14
|
13
|
0.09
|
Kid growth
|
0
|
0
|
9
|
0.02
|
0
|
8
|
23
|
0.07
|
Age at sexual maturity
|
1
|
5
|
2
|
0.03
|
6
|
24
|
24
|
0.17
|
Kidding interval
|
1
|
25
|
16
|
0.13
|
0
|
12
|
12
|
0.07
|
Twining ability
|
10
|
25
|
15
|
0.18
|
4
|
26
|
13
|
0.14
|
High milk yield
|
0
|
8
|
24
|
0.07
|
1
|
1
|
5
|
0.02
|
I= index and R= rank |
Mating and Castration
The percentage of households who practiced buck castration and the method of castration used are presented in Table 4. The proportion of households who practiced castration and the average age of castration varied from place to place. As per the respondents, 79 and 74% practiced castration in Abaya and Galan districts, respectively. About two-thirds of respondents practiced the modern method of castration indicating that goat keepers in the study districts have access to local veterinary services. A similar result was reported by Mahilet (2012) in Eastern Hararghe. Indeed, this is a common practice by livestock keepers where the respondents indicated that castration is a value-adding process (fattening) in both districts to avoid weight loss due to mating that eventually benefits farmers earn better prices at marketing. Moreover, respondents argued that a castrated goat has fewer odors, produces tasty and tender meat than uncastrated goats. Almost all respondents in both districts report selecting the breeding buck for future generations. One of the drawbacks observed in both districts was that there was no controlled mating practice. This leads to a high inbreeding rate that eventually leads to population inbreeding depression (Maiwashe et al., 2006).
Table 4. Breeding practices of goat farmers
|
Abaya N (%)
|
Galan N (%)
|
Overall N (%)
|
|
Yes
|
No
|
Yes
|
No
|
Yes
|
No
|
1. Do you identify a sign of heat?
|
89(98.9)
|
1(1.1)
|
62(68.9)
|
28(31.1)
|
151(83.9)
|
29(16.1)
|
2. Do you allow others to mate your doe?
|
90(100)
|
-
|
90(100)
|
-
|
180(100)
|
-
|
3. Did buck mate his
|
90(100)
90(100)
90(100)
|
-
-
-
|
90(100)
90(100)
90(100)
|
-
-
-
|
180(100)
180(100)
180(100)
|
-
-
-
|
4. Do you select breeding bucks?
|
90(100)
|
-
|
88(97.7)
|
2(2.2)
|
178(98.9)
|
2(1.2)
|
5. Do you practice castrate buck?
|
71(78.9)
|
19(21.1)
|
67(74.44)
|
23(25.5)
|
138(76.7)
|
42(23.3)
|
6. Methods of castration use
|
|
|
|
|
|
|
70(77.8)
30(33.3)
|
|
59(65.6)
31(34.4)
|
|
59(65.6)
31(34.4)
|
|
N= number of household
Effective Population Size and Rate of Inbreeding
The effective population size (Ne) and the rate of inbreeding (ΔF) calculated for goat flock in the study area are presented in Table 5. Effective population size is a measure of genetic variability within a population, with large values of Ne indicating more variability and small values indicating less genetic variability. In this study, the estimate of effective population size (Ne) was 2.2 and 1.73 in Abaya and Galan districts, respectively. The rate of inbreeding in the study area is beyond the threshold level or maximum acceptable level (0.063) Armstrong (2006). This was due to small effective population size, utilization of breeding buck born within the flock, and uncontrolled mating. This finding is comparable to that of Tesfaye (2010) who report the inbreeding coefficient of Afar sheep in Ethiopia (0.20) and Belete (2013) who reported 0.21 from a Bale goat population.
Table 5. The inbreeding rate and effective population size
District
|
When flock are not mixed
|
|
Nm
|
Nf
|
Ne
|
ΔF
|
Abaya
|
0.72
|
2.32
|
2.2
|
0.22
|
Galan
|
0.73
|
1.07
|
1.73
|
0.29
|
Measures of Reproductive Performance
The reproductive performance of the goat in the study area is summarized in Table 6. The overall mean reproductive lifetime of the female goat was 7.2 ±.12 years within this year a doe could produce around 12.1±.22 kids. Age at first kidding (AFK) can be defined as the age at which does give birth for the first time. The overall Age at first kidding (AFK) of goats in the study area was 12.11±.40 months. This is in agreement with the study of Alefe (2014) who reported AFK of indigenous goats in the Shabelle zone, Ethiopia was about 14.75 months, and Gebrekiros (2014) who reported AFK of 12-18 months for Begait goats. However, Adugna (1998) reported AFK of 19.5 months for Kochore goats in SNNP. Age at first kidding in Ethiopian breeds is a well-known trait at the farm level and it ranges from 12-24 months (Girma, 2008). Age at first kidding is highly variable and dependent on the growth rate and management practices (Song and Sol, 2006).
The overall average kidding interval (KI) in months for Abaya and Galan goats was 7.83±.13. This is contradictory with a report of Mahilet (2012) who reported a kidding interval of 6.56±.04 months for Eastern Hararghe goats. According to studies of Belete (2013); Alefe (2014) and Tesfaye et al. (2012) KI interval ranges from 8-11.7 months for different breeds of goats in Ethiopia. Moreover, poor nutrition and prolonged suckling resulted in the longer interval between kidding. The overall reproductive lifetime of male goats was also 4.5±0.77 years which is shorter than their female counterparts. This is mainly due to the fact that, except bucks used for breeding, most males are castrated and do not stay long in the flock as they were sold. This result is disagreeing with other previous studies such as Belete (2013) and Alefe (2014) who reported that the reproductive life span of the buck was 8.6 and 6.5 years in Bale and Shabelle zones, respectively.
Table 6. Reproductive parameters of sampled goats
Reproductive trait
|
Abaya
|
Galan
|
Overall
|
|
Mean + SE
|
Mean + SE
|
Mean + SE
|
Average age at first kidding (months)
|
11.99±.612
|
12.17±.248
|
12.11±.398
|
Average kidding interval (months)
|
7.62±.122
|
8.04±.243
|
7.83±.136
|
The average reproductive life span of doe (years)
|
7.58±.167
|
6.74±.170
|
7.16±.123
|
Average servicing age of buck in a flock (years)
|
4.37±.127
|
4.6±.087
|
4.5±.077
|
The average number of kid crops per doe (Number)
|
12.02±.381
|
12.20±.221
|
12.11±.220
|
Prolificacy of Goat
The prolificacy of the goat in the study area is summarized in Table 7. Based on the respondent's opinion, a higher twinning rate of about 72.2% was reported, with only 26.66% single births. This implies that the goat population in the study area is highly prolific and warrants closer attention for selection. This result is disagreeing with the similar production system study of Mahilet (2012) who describes single birth as highly predominant in Eastern Hararghe goats. Also, the present result is significantly higher than the twining rate report of Woito Guji goats, which was only 16%, and Arsi Bale goats breeds (18%) (Farm-Africa, 1996).
Table 7. Prolificacy of goat
Types of birth
|
Abaya
|
Galan
|
Overall
|
|
N
|
%
|
N
|
%
|
N
|
%
|
Single
|
28
|
31.11
|
20
|
22.22
|
48
|
26.66
|
Twins
|
61
|
67.78
|
69
|
76.66
|
130
|
72.22
|
Triplets
|
1
|
1.11
|
1
|
1.11
|
2
|
1.11
|
The purpose for Keeping Goats
The purpose of keeping a goat in the study area is shown in Table 8. The main purpose of keeping a goat in Abaya was mentioned as sources of income, insurance risk (live asset), and meat consumption whereas sources of income, meat, and saving are primary purposes in Galan. Traditionally, goat keepers in the study district believe that eating goat meat and its by-product (blood, brain, and small intestine) have some medicinal values. Milk is consumed by goats in both districts. This finding was disagree with the result of Ahmed et al. (2015) who reported that milking was not accustomed by the community of Horro Guduru district of Wolega zone. like in the case of some pastoral communities (pastoral and agro-pastoral production system) in Ethiopia, goat milk is consumed. The utilization of goat manure as soil fertilizer is higher in Galan than in Abaya indicating that farmers in Galan practice crop cultivation as their supplementary farm activities as compared to the pastoral system practiced in Abaya.
Goat milk is consumed in both districts, indeed milking goat is a common practice in the pastoral and agro-pastoral production systems. Group discussants in districts believed that goat milk has medicinal value for children against ascarids. Moreover, it was reported that goat milk increases the appetites of the children. It was reported that specifically goat blood is given to women immediately after birth to cure lesions and overcome anemia due to heavy blood loss.
Table 8. Purpose of keeping a goat
Purpose
|
Abaya
|
Galan
|
|
R1
|
R2
|
R3
|
I
|
R1
|
R2
|
R3
|
I
|
Meat
|
12
|
18
|
30
|
0.19
|
8
|
27
|
30
|
0.20
|
Milk
|
3
|
10
|
11
|
0.07
|
0
|
2
|
0
|
0.01
|
Feels for hats and mattresses
|
1
|
1
|
0
|
0.01
|
7
|
3
|
0
|
0.05
|
Sale (cash income)
|
31
|
31
|
16
|
0.32
|
55
|
17
|
3
|
0.37
|
Insurance for risk
|
27
|
24
|
10
|
0.26
|
1
|
0
|
12
|
0.03
|
Ceremonies(gift/wedding, sacrifices)
|
1
|
0
|
2
|
0.01
|
0
|
0
|
0
|
0.00
|
Prestige and socio-culture value
|
1
|
1
|
1
|
0.01
|
5
|
2
|
2
|
0.04
|
Savings
|
4
|
3
|
7
|
0.05
|
10
|
18
|
31
|
0.18
|
Collateral(for loan, compensation)
|
1
|
0
|
6
|
0.02
|
0
|
0
|
0
|
0.00
|
Dowry
|
0
|
1
|
0
|
0.00
|
0
|
0
|
0
|
0.00
|
rituals
|
2
|
1
|
1
|
0.02
|
0
|
0
|
0
|
0.00
|
Manure as fertilizer
|
2
|
0
|
6
|
0.02
|
0
|
16
|
12
|
0.08
|
Skin for home use
|
5
|
0
|
0
|
0.03
|
4
|
5
|
0
|
0.04
|